Nitroparaffins are commercially produced by the vapor-phase nitration of hydrocarbon feedstock. The nitration generally produces a variety of products depending upon the reaction conditions and the feedstock structure. For instance, the commercial vapor phase process for propane nitration results in a mixture of four nitroparaffin products (nitromethane, 1-nitropropane, 2-nitropropane, and nitroethane) in essentially fixed relative concentrations.
Nitroparaffin products of the commercial vapor-phase nitration process are known to suffer from undesirable color formation during storage. To address this problem, the commercial process requires a chemical wash step prior to nitro compound distillation in order to eliminate color-forming impurities that cause discoloration. However, there are several disadvantages to current commercial processes, including the necessity, in some processes, for deepwell disposal of used wash solution. Another disadvantage is the tendency of commercial wash solutions to react with the nitroparaffins, resulting in a nitroparaffin yield loss. There is a need, therefore, for improved chemical wash processes.